This study investigates mythologemes core mythic concepts encoded in language in Kazakh and English cultures and examines their role in shaping cultural identity. Drawing on linguoculturology and cultural semantics, the research analyzes such figures as “Zhalmauyz Kempir”, “Azireyil”, “the Banshee”, and “the Grim Reaper”. A comparative qualitative design was employed, incorporating data from the British National Corpus, the national corpus of the Kazakh language, literary texts, and folkloric sources. Each mythologeme was examined in its linguistic and cultural context, with particular attention to patterns of lexicalization and metaphorization, and subsequently contrasted across the two languages. The findings demonstrate that although these figures share universal archetypal features primarily as representations of death or evil their linguistic realizations and semantic nuances are culturally specific. For instance, in Kazakh tradition, “Zhalmauyz Kempir” is portrayed as an active, child-devouring entity, whereas the Celtic “Banshee” functions as a passive harbinger of death. Similarly, “Azireyil” in Kazakh discourse evokes the notion of divine fate, while the English “Grim Reaper” embodies the personification of fearful inevitability. Despite cultural differences, both sets of mythologemes remain productive in contemporary language through idioms, metaphors, and media discourse, functioning as dynamic carriers of collective memory and value systems. The study demonstrates that mythologemes operate as adaptable linguistic-cultural constructs that preserve core symbolic meanings while continuously adjusting to evolving social contexts. This comparative analysis highlights how shared mythic motifs are reinterpreted within distinct cultural-linguistic frameworks, thereby reinforcing cultural identity, ethical norms, and national narratives.